(-2x^2)^3*3x is -24x^7 but i keep getting -6x^6 so can someone explain to me where i am going wrong?

(-2x^2)^3*3x is -24x^7

exponents first

(-2x^2)^3

(-2)^3 x^(2)^3  (when raised to a power multiply the powers on the exponent)

(-2) *(-2) *(-2)*x^(2*3)

-8 x^6

-8 x^6 * 3x

-8*3 * x^6 *x  (when multiplying  add the exponents)

-24 x^(6+1)

-24 x^7

6√5/25 = 6√5/(√5)^4 = 6/(√5)^3 (invalid)

30/√5 = 6*(√5)^2/(√5) = 6√5 (invalid)

36/√30 =  6*(√6)^2/(√5*√6) = 6√6/√5 (invalid)

6√5/5 = 6√5/(√5)^2 = 6/√5 (valid)